Here's some good news: despite our short collective attention span, despite the fiscal-cliff debacle dominating the headlines shortly after the Newtown shooting, the U.S. scourge of gun violence is still part of the national conversation. Now, every time I hear a public official mention Newtown and Aurora but not Chicago—which experienced a startling spike in gun homicides in 2012, mostly in poor, black neighborhoods—I'm ashamed at the implication that some killings deserve more shock and outrage than others. Still, whatever it takes to motivate people to take on the pro-gun lobby, I'm grateful to see it happening.